scsi: fnic: remove redundant assignment of variable rc

Variable ret is initialized to a value that is never read and it is
re-assigned later and immediately returns. Clean up the code by removing
rc and just returning 0.

[mkp: typo]

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Karan Tilak Kumar <kartilak@cisco.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>